Single-reel tape cartridges used for backing up computers are known in the art.
Single-reel tape cartridges are constructed by installing a tape reel having a large diameter in an approximately rectangular cartridge housing in a rotatable manner, and winding a tape-like recording medium around the tape reel, the inner end of the tape-like recording medium being attached to the periphery of the tape reel. The outer end of the tape-like recording medium is extracted through a tape-passage hole formed at the front side of cartridge housing at one end thereof and is wound around the periphery of a take-up reel. A central region of the extracted tape-like recording medium is loaded around a rotating head drum, and sound data and image data are recorded on the tape-like recording medium by the rotating head drum while the tape-like recording medium is being wound around the take-up reel.
When a single-reel tape cartridge is loaded in a recording/playback apparatus, a tape-like recording medium contained in the cartridge must be lead out and wound around a take-up reel located in the recording/playback apparatus. To achieve this, the tape-like recording medium is attached to a leader block, which is pulled out by a tape-extracting mechanism and transferred by a transferring mechanism.
When the leader block is disposed inside a cartridge housing, it is placed inside a leader block receiver, which is large enough to store the leader block. The leader block receiver is formed at a position close to an opening formed in the cartridge housing, and the opening is closed while the leader block is placed inside the leader block receiver.
In addition, when the leader block is disposed inside the take-up reel, it is placed inside a leader block retainer, which is formed in a reel hub of the take-up reel in such a manner that the leader block can be inserted therein. The leader block retainer is formed by cutting out parts of flanges and the reel hub of the take-up reel toward the center, and the leader block transferred by the transferring mechanism of the recording/playback apparatus is inserted in the leader block retainer. The leader block retainer is provided with an open end having a large width through which the leader block is inserted.
On the other hand, the applicant of the present invention has applied a patent for a library apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2000-57662. The library apparatus disclosed in this publication uses double-reel tape cartridges such as Advanced Intelligent Tape (AIT) cartridges and Digital Video (DV) cartridges. Each of the double-reel tape cartridges is provided with a pair of changer grips at the right and left sides thereof at positions closer to the rear side than to the front side. The changer grips are formed as concavities having a trapezoidal shape.
In addition, a pair of opening/closing hand arms are mounted on a tray used for transferring the tape cartridges. The opening/closing hand arms are able to clamp each of the tape cartridges stored in a magazine by the changer grips and carry it between the magazine and the tray and between the tray and a magnetic recording/playback apparatus. Accordingly, the tape cartridges are exchanged automatically.
However, since single-reel tape cartridges of the known art are not provided with changer grips, they require complex transfer mechanism when used in library apparatuses in which tape cartridges are exchanged automatically.
On the other hand, some double-reel tape cartridges (for example, AIT cartridges and DV cartridges used in tape streamers) contain a memory module at the rear side thereof, that is, at the side opposite to the front side in which a tape-passage hole, which is opened and closed by a front lid, is formed. The memory module stores management information of a tape-like recording medium which serves as a recording medium.
A tape cartridge of this type is inserted horizontally through a cartridge-receiving hole formed in a front panel of a magnetic recording/playback apparatus from the side at which the front lid is formed. Then, the tape cartridge is horizontally drawn into the magnetic recording/playback apparatus by a cassette compartment, moved vertically downward, and loaded by being engaged with a pair of reel shafts from the upper side thereof.
When the tape cartridge is loaded, the memory module mounted at the rear side of the tape cartridge is placed in front of a memory-access module, which is mounted inside the front panel of the magnetic recording/playback apparatus at a position below the cartridge-receiving hole.
Then, the tape-like recording medium contained in the tape cartridge is extracted through the tape-passage hole formed at the front side of the tape cartridge and is loaded around the periphery of a rotating head drum by a tape-loading mechanism. In addition, the management information for the tape-like recording medium stored in the memory module is read out by the memory-access module by an accessing method similar to that of a barcode reader, etc. Then, an information recording and/or playback operation is performed on the basis of the management information obtained as described above.
On the other hand, a plurality of kinds of tape cartridges containing tapes with different storage capacities and storage characteristics have been provided, and they are distinguished from each other by forming identification holes in cartridge housings.
However, in tape cartridges containing a single tape reel, the beginning of tape (BOT) and the end of tape (EOT) cannot be detected from the tape-like recording media themselves. More specifically, the tape-like recording media are formed uniformly from the beginning to the end.
A tape cartridge containing a tape-like recording medium as described above includes a reel-lock which prevents the tape reel from rotating freely when the tape cartridge is not loaded in a drive apparatus.
In addition, a reel lock disengaging member is disposed inside the drive apparatus, and a reel lock disengaging member receiving groove, in which the reel lock disengaging member is inserted, is formed in the cartridge housing at one of the side surfaces which are parallel to the direction in which the cartridge is inserted into the drive apparatus. The reel lock disengaging member receiving groove extends from the front end in the direction in which the cartridge is inserted into the drive apparatus toward the other.
The reel lock disengaging member receiving groove is formed by cutting out a part of the cartridge housing at one of the side surfaces thereof so as to form a groove which has a bracket shape in cross-section and which is open at the front end in the direction in which the cartridge is inserted into the drive apparatus and extends toward the other end. The reel lock, which is disposed inside the cartridge housing and prevents the tape reel from rotating freely, faces toward the outside through the reel lock disengaging member receiving groove.
When the tape cartridge is inserted into the drive apparatus, the reel lock disengaging member, which is disposed inside the drive apparatus, is inserted through the reel lock disengaging member receiving groove and contacts the reel lock.
The tape reel, which is rotatably installed in a tape reel receiver, includes a reel hub and upper and lower flanges formed at the upper and lower ends of the reel hub. The tape-like recording medium is wound around the reel hub while one end thereof is attached to the reel hub, and windings of the tape are aligned by the upper and lower flanges.
Engaging teeth, which become engaged with the reel lock, are formed around the entire periphery of the upper flange.
The reel lock, which prevents the tape reel from rotating freely by becoming engaged with the engaging teeth, includes a locking member having a restraining projection which becomes engaged with the engaging teeth. The locking member is constantly pressed toward the tape reel by a torsion spring or the like, and restrains the rotation of the tape reel by becoming engaged with the engaging teeth formed on the upper flange.
The locking member faces toward the outside through the reel lock disengaging member receiving groove, and when the tape cartridge is inserted into the drive apparatus, the reel lock disengaging member disposed inside the drive apparatus is inserted through the reel lock disengaging member receiving groove and contacts the locking member.
When the reel lock disengaging member contacts the reel lock, the reel lock is pressed in a direction in which the reel lock becomes disengaged from the tape reel. Accordingly, when the tape cartridge is inserted in the drive apparatus, the tape reel becomes free to rotate, so that the tape-like recording medium can be transferred to the take-up reel.
When the tape cartridge is ejected from the drive apparatus, the reel lock disengaging member is removed from the reel lock disengaging member receiving groove, so that the reel lock is moved toward the tape reel by the pressing force applied by the torsion spring. Accordingly, the reel lock becomes engaged with the engaging teeth formed on the upper flange and restrains the rotation of the tape reel.
Accordingly, the reel lock prevents the tape reel from rotating freely inside the cartridge housing when the tape cartridge is not used.
The leader block retainer and the leader block receiver formed in the take-up reel and the leader block receiver, respectively, must be constructed such that the leader block can be inserted and extracted. Accordingly, when the leader block is disposed in the leader block retainer, a predetermined amount of clearance is provided between the leader block and the leader block receiver and between the leader block and the leader block retainer.
Accordingly, the leader block cannot be reliably positioned inside the take-up reel and the cartridge housing, and rattling easily occurs.
In addition, the pair of changer grips formed in AIT cartridges, DV cartridges, etc., of the known art are constructed as concavities having a trapezoidal shape and do not extend from end to end in the vertical direction. Accordingly, the pair of opening/closing hand arms mounted on the tray must perform an opening/closing operation to clamp the cartridge by the changer grips.
Accordingly, the opening/closing hand arms must perform both a sliding operation for transferring the tape cartridge between the magazine and the tray and between the tray and the magnetic recording/playback apparatus and the opening/closing operation for clamping the tape cartridge. Therefore, there is a problem in that the mechanism and control processes of the opening/closing hand arms are extremely complex and high costs are thereby incurred.
In addition, when the memory module is disposed at the rear side of the tape cartridge, the direction from which the memory-access module is able to access the memory module is limited to the rear side of the tape cartridge. Accordingly, the position at which the memory-access module can be placed inside the magnetic recording/playback apparatus is limited to the area between the rear surface of the tape cartridge loaded in the magnetic recording/playback apparatus and the inside surface of the front panel. Therefore, the depth of the magnetic recording/playback apparatus, that is, the size thereof in the front-rear direction, is increased.
Furthermore, there is a problem in that when the magnetic recording/playback apparatus is of the type in which the rear side of the tape cartridge projects outside while the tape cartridge is loaded in the magnetic recording/playback apparatus, the memory module cannot be accessed by the memory-access module.
In addition, as described above, in tape cartridges containing a single tape reel, the beginning of tape (BOT) and the end of tape (EOT) cannot be detected from the tape-like recording media themselves. More specifically, the tape-like recording media are formed uniformly from the beginning to the end.
In addition, since the end of the tape-like recording medium is merely wound around the hub of the tape reel in such a tape cartridge, when the tape-like recording medium is extracted by more than a predetermined length, the end of the tape-like recording medium becomes separated from the tape reel and is pulled out from the cartridge.
When the end of the tape-like recording medium is pulled out from the cartridge, the tape-like recording medium becomes entirely wound around the take-up reel in the magnetic recording/playback apparatus, so that it becomes extremely difficult to take the tape-like recording medium out from the magnetic recording/playback apparatus. In addition, that tape-like recording medium probably cannot be used afterwards.
In order to avoid this, the operation of extracting the tape-like recording medium must be stopped while the tape-like recording medium is still wound around the tape reel at a sufficient length. Accordingly, the tape-like recording medium cannot be fully utilized as a data region to the end.
In addition, in the case in which the identification holes are formed in the cartridge housing in order to identify the kind thereof, positions at which the identification holes can be formed are limited, so that there is a limit to the number of kinds which can be represented by the identification holes. Accordingly, parameters of electrical characteristics and parameters used for mechanical control are not always suitable for that tape, and tape-like recording media formed of similar materials are classified into the same group.
Accordingly, the recording/playback system cannot be controlled with optimum parameters, so that tape-like recording media cannot be used at their best performances.
In addition, when tape cartridges which do not contain memories storing management information are used, tape streamer drives require information such as the tape length, the tape thickness, etc., in order to handle the tape cartridges (to manage the remaining capacity, to control the drive, etc.).
When an unformatted (blank) tape is used, it is necessary to run the tape-like recording medium at an original speed, measure the reel diameter, and calculate the tape length on the basis of the reel diameter. Accordingly, a long time is required for loading the tape-like recording medium, and the tape thickness must be determined in advance.
In the case in which a tape cartridge containing a formatted tape is used, information obtained in advance by performing measurement is recorded in a system area of the tape-like recording medium when the tape is formatted. The drive obtains the information, such as the tape length and the tape thickness, by reading the system area of the tape-like recording medium.
However, in this case, the drive must determine parameters suitable for the electrical characteristics of the tape by trial-and-error in order to read the system area of the tape-like recording medium. Accordingly, the tape-streamer drive of the known art has a problem in that a long time is required for loading the tape.
In addition, in the tape cartridge of the known art, the reel lock, which becomes disengaged from the tape reel when the tape reel is to be released, must face toward the outside through the reel lock disengaging member receiving groove.
Accordingly, not only when the cartridge is inside the drive apparatus but also when it is ejected therefrom, the interior of the cartridge housing always faces toward the outside through the reel lock disengaging member receiving groove.
Therefore, there is a risk in that dust will enter the cartridge housing and damage the tape-like recording medium so that the recording/playback characteristics of the tape-like recording medium are degraded.
In addition, when the tape cartridge is inserted in the drive apparatus, it may be inserted inversely by accident. In such a case, there is a risk in that a cartridge holder in the drive apparatus will be damaged or malfunction of the drive apparatus will occur.